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11 July 2007 AGE-NC Project No. 98-0533 Page 4 of 5 3.1. SOIL BORING ADVANCEMENT Three of the probe borings will be advanced using a van-mounted Geoprobe 5400 direct-push probing unit equipped with 1.25-inch probing rods. The Geoprobe advances soil borings using a hydraulic hammer to drive soil sampling tools to specified depths. A total of six probe borings will 3 be advanced using a hand held gas vapor probe equipped with dedicated gas vapor tips. The hand P1 elk d held gas vapor probe uses a slide hammer to drive soil sampling tools to specified depths. One soil boring will be advanced with soil hand auger and soil sample will be collected with a drive J soil sampling tool and six by two inch stainless steel sleeve. 3.2. SOIL SAMPLE COLLECTION AND ANALYSIS Soil borings will be sampled at two feet bsg and five feet bsg with a 1.125-inch Geoprobe or hand driven soil sampling assembly loaded with four six-inch or six by two inch stainless steel sleeves. Upon sample retrieval,the ends of the second sleeve will be covered with Teflon sheets,capped and sealed with tape. Appropriately sealed and labeled samples will be placed in a chilled container under ice and transported under chain-of-custody procedure to a DHS-certified laboratory.Each sample sleeve will be labeled with the boring designation,depth,time,date and sampler's initials. Soils encountered in the borings will be visually classified by an AGE geologist in accordance with the Unified Soil Classification System(USCS).Additionally, soil samples will be field-screened for the presence of volatile organic compounds using an organic vapor meter(OVM),equipped with photo-ionization detector(PID). i I V,d -(� 1 � 3.3. SOIL-VAPOR SAMPLE COLLECTION AND ANALYSIS S Soil-vapor samples will be a obtained at depths of approximately 4.5 to 5 feet bsg in each soil boring. Two soil-vapor samples will be collected using a Geoprobe soil vapor assembly,and six soil-vapor samples will be collected using a hand held gas vapor probe. An expendable vapor point will be placed into a point holder at the bottom of a string of 1-inch diameter (Geoprobe), or 5/5-inch diameter(hand held gas vapor probe),hollow drive rods.The assembly will then be advanced to the specified depth and retracted six inches in order to engage the expendable point and expose a column of strata from which soil vapor can be extracted. A Geoprobe post run tubing adapter equipped with an O-ring to ensure a vacuum-tight seal is then attached to a'/4-inch diameter,single-use,disposable polyethylene tubing. The sampling tube is then lowered through the center of the hollow drive rods and secured by threading into the expendable point holder. The probe rod is retracted a minimum Advanced GeoEnvironmental,Inc.